Process for the degreasing of raw wool and other textile fibers



Patented June 25, 1929.

UNITED STATES ALFRED ENGELHARDT,

1,718,548 PATENT OFFICE.

0F WIESDORF, NEAR COLOGN E-ON THERHIN E, GERMANY, AS-

THE-MAIN, GERMANY.

The present invention concerns the degreasing of raw wool or other textile fibers by the application of cyclohexanone or its homologues.

For some considerable time attempts have been made to effect the washing of wool by the aid of organic fat solvents instead of by the hitherto employed method of using soap exclusively, since it has been found that in this manner the wool fiber is protected to a greater extent and also a more valuable wool fat is obtained. However, this problem hitherto had not been solved successfully from a technical and economical point of view, since none of the solvents proposed for this purpose possesses all the properties required by a rational large scale operation.

The properties of such as follows:

It should possess a high solvent capacity for wool fat and wool wax at ordinary temperature and should be sufficiently mobile. It should be stable towards boiling dilute alkalies. It is, further, indis .)ensable for the safety of the process that the solvent should not emit any easily inflammable vapors and a solvent should be essential that it should not incur losses due to too great volatility, neither should it have a corrosive action on metals. It is also of great importance that the solvent should be to a certain extent soluble in Water, in order to facilitate a simple execution of the washing process.

proposed such as, for carbon tetrachloride, triacetone, acetic acid ester and carbonic acid ester of methanol and ethyl alcohol, do not satisfy these fundamental requirements.

be present invention is based on the discovery of the fact that cyclohexanone and its omologues, such as, for example, methyl cycloh-exanone, possess all the'above properties and are thus excellently suited to application as de-greasing agents for wool. For example, the essential characteristics of cyclohexan one are as follows:

Its capacity for dissolving lwool fat; and wool wax at ordinary temperature equals that of benzene, to which it also corresponds as re gards mobility. It boils at 155 jC., and the vapor tension at ordinary temperature is no and in Germany March 12,

higher than that of water. Since the flash point is 39 C. (the flash point of benzene being 8 (1), the technical application involves practicaly no danger owing to inflamniability. Cyclohexanone does not exert an unfavorable physiological action under the conditions obtaining in actual practice. No substantial losses are to be feared from vaporization and it does not decompose on heating with dilute alkaline solutions. One part of cyclohexanone dissolves in about 11 parts of water, from which solution it can be isolated by salting out, or by extraction with oils. The solubility in water effects an easy and efficient washing of the Wool with the result that any adherent residues of solvent are completely removed after extraction.

By the application of cyclohexanone as solvent a soft pure wool is produced, which retains its original curly nature and is equivalent in quality to the best products obtained from raw wool by extraction with other or ganic solvents.

The invention will be more fully described by reference to the following, and subsequent, examples Eaw-mple 1.The suint wool is freed from dust by beating and loosely compressed by a punch or plunger in cylindrical containers about 4 ft. in diameter and 15 ft. high, wherein the wool is carried 011 metal screen plates located about 10 cm. above the floor of the container. Cyclohexanone is then passed from below into the container and passes upwardly through the wool and is saturated with'wool fat, whereby the solvent takes up wool fat up to 9% by weight of wool fat. The wool fat solution passes from the extraction apparatus through a lateral discharge. The wool fat is obtained from the saturated extraction. When the wool fat content of the cyclohexanone passing from the washing apparatus has dropped to 0.2% by welght, extraction is terminated. The cyclohexanone 1s passed from the apparatus below, whereby the wool is strongly compressed by the plunger. The wool is then loosened by raising the plunger and the cyclohexanone adhering thereto is washed therefrom with Wafat. For the purpose of or thereabouts.

ter in the same manner as the wool fat was previously dissolved out, whereby the wool is repeatedly compressed and loosened. The suint salts are also dissolved out of the wool during the operation described.

After this extraction procedure the wool is washed moderately with soap solution to remove the last traces of dirt, rinsed moderately with water, and then dried by hot air.

In such cases where a particularly mild extraction of open wool is required in order to retain a slight amount of fat in the capillaries of the cellular fibers, there may be employed cyclohexanone, or a homologue thereof, containing a regulated, predetermined small quantity of fat, as, for example, wool the present invention, by a predetermined small quantity is meant a content of the order of one percent Or, there ma be employed a mixture comprising cyclo exanone and other water-soluble organic solvents, the latter solvents having only a relatively small solvent capacity 'for Wool fat and particularly for wool wax; e. g., alcohol, glycerin or the like. I

Example 2.Beaten Merino suint wool is passed in counter-current to a solution of 0.2% by weight of wool fat in a mixture of parts by weight of methyl-cyclohexanone and 20 parts by weight of 96% ethyl alcohol, in three Leviathan washers, whereby the wool fat is remove-d from the wool and a solutioncontaining about 6% wool fat is obtained. The wool fat is separated from this solution by distilling off the solvent. After the fat is removed, the wool is freed of the adhering solvent residue and of the suint salts by washing with water in two connected Leviathan washers. The wool is treated with a dilute soap solution to remove the last traces of dirt, rinsed with clear water, and then dried with hot air.

It will depend entirely on the particular kind of wool, whether the raw wool is first subjected to washing with an aqueous liquid, as, for example, water, or an ordinary aqueous soap solu tion-, in order to extract the potassium salts, andthen is further extracted in a moist or dry condition with cyclohexanone alone or in admixture with other organic solvents, or whether the raw wool is subjected to extraction direct, and, if necessary," 's afterwards subjected to treatment with an aqueous liquid. In all these cases, cyclohexanone achieves a thorough de-greasing and produces a soft wool which is not matted or stringy.

Example 3.Suint wool is freed from dust by beating, loosened up, and the salt removed byallowing water to trickle thereon while it is advanced on a perforated conveyor band.

' After expressing the greater quantity of the water, the wool passes through three Leviathan washers, through which methyl-cycloterials, as, for example,

last traces of dirt, the soap rinsed out, and

the washed wool is dried.

' The wool fat is recovered from the wool fat solutions in the customary manner by distilling off the cyclohexanone under ordinary or reduced pressure as a residue of yellowish coloration. The solvent residues adhering to the wool after the extraction can be replaced by water according to the known method for carbon'tetrachloride extraction, the process being of course particularly easily effected owing to the water solubility of the cyclohexanone.

The washing process with cyclohexanone is carried out on the large scale using the apparatus customary for W001 washing. \Vhen. the process is subject to bein interrupted, as, for example, in small woo washing plants, upright cylinders are employed, while for continuous large scale working the well known so-called Leviathan apparatus can be utilized. Owing to the intensive solvent action of the cyclohexanones a much improved washing performance is obtained over that of the customary soap process.

cyclohexanone and its homologues can also be employed with success as solvents in other branches of the textile industry for the purpose of removing fats or oils from textile mafrom the spools. after spinning yarns, similar advantages exhibiting themselves as in the de-greasing of raw wool.

I claim:

1. Process for the de-greasing of raw wool or other textile material which comprises washing the raw wool or other textile material with a solvent comprising a compound having the general formula:

wherein X represents hydrogen or a monovalent aliphatic radicle.

terial with a solvent mixture containing a compound having the general formula:

wherein X represents hydrogen or a monovalent aliphatic radicle, a water-soluble organic solvent having only a relatively small solvent capacity for wool fat and wool wax, and a regulated, predetermined small amount of fat.-

5. Process for the de-greasing of raw WOOl or other textile material which comprises washing the raw wool or other textile material with a solvent mixture containing a compound having the general formula:

wherein X represents hydrogen or a monovalent aliphatic radicle, and a regulated, predetermined small amount of fat.

6. Process for the de-greasing of raw wool or other textile material which comprises washing the raw wool or other textile material with a solvent comprising a compound having the general formula:

wherein X represents hydrogen or a monovalent aliphatic radicle, separating at least a part of the solvent from the wool and thereafter washing the Wool with an aqueous liquid.

7. Process for the de-greasing of raw wool or other textile material which comprises preliminarily washing the raw wool or other textile material with an aqueous liquid, and

thereafter washing the resulting moist wool with a solvent containing a compound of the general formula:

wherein X represents hydrogen or a monovalent aliphatic radicle.

8. Process for the de-greasing of raw wool or other textile material which comprises preliminarily washing the raw wool or other textile material with an aqueous liquid, thereafter washing the resulting moist wool with a solvent containing a compound of the general formula:

wherein X represents hydrogen or a monovalent aliphatic radicle, and finally washing the wool with an aqueous liquid.

In testimony whereof, I aflix my signature.

ALFRED ENGELHARDT. 

